There are a total of 141 collectibles in Bioshock Infinite. 80 Voxophones, 24 Infusion Upgrades, 37 Telescopes and Kinetoscopes (Sightseer Collectibles).Finding all of them will earn you three trophies / achievements:Eavesdropper [Silver / 50G]Infused with Greatness [Bronze / 25G]Sightseer [Bronze / 50G]

There is chapter select and you can replay chapters after beating the game to pick up missing collectibles. However, there is no collectible counter per chapter / area and everytime you replay a chapter, the collectibles will respawn! So there is no way to tell which ones you already found. Make sure to get all of them in correct order!